While carnitine is needed for good health, you probably have all that you need. People with genetic problems and some diseases — as well as pre-term babies — may have low levels. L-carnitine supplements may help them.

L-carnitine is a popular supplement for athletes. However, studies have not found that it helps improve sports performance, muscle adaptations, or endurance.

L-carnitine may help certain patients survive heart attacks, have less heart rhythm disturbances, and less chest pain.  When added to regular medication therapy, carnitine may improve health in people with peripheral artery disease, but further research is needed.

It is thought that patients with cancer may become carnitine deficient, and carnitine supplementation may be helpful to reduce chemotherapy side effects.

Researchers are still studying to find out if carnitine can improve memory and thinking problems in older people.

There’s no standard dose of L-carnitine. Ask your healthcare provider for advice.